Helium Backup
From Just Solve the File Format Problem
Helium backups are backups made by the Helium (previously Carbon) backup software by ClockWorkMod, who also made Vyzor and CWM recovery.
Details
/storage/emulated/0/carbon/ contains subdirectories of package ids.
Package IDs of interest: com.android.providers.telephony contains call related data. com.android.providers.userdictionary contains… you guessed it. User dictionary data.
Each folder contains 4 files. Both are titled the package ID. The file of interest is the .ab file, which is an Android ADB Backup, second is a json with metadata. There is also the app icon an a nomedia file.
